Commit 146ed598 authored by Ingo Molnar's avatar Ingo Molnar

x86/fpu: Move the no_387 handling and FPU detection code into init.c

Both no_387() and fpu__detect() run at boot time, so they belong
into init.c.
Reviewed-by: default avatarBorislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 4445e6e9
......@@ -581,37 +581,3 @@ int dump_fpu(struct pt_regs *regs, struct user_i387_struct *fpu)
EXPORT_SYMBOL(dump_fpu);
#endif /* CONFIG_X86_32 || CONFIG_IA32_EMULATION */
static int __init no_387(char *s)
{
setup_clear_cpu_cap(X86_FEATURE_FPU);
return 1;
}
__setup("no387", no_387);
/*
* Set the X86_FEATURE_FPU CPU-capability bit based on
* trying to execute an actual sequence of FPU instructions:
*/
void fpu__detect(struct cpuinfo_x86 *c)
{
unsigned long cr0;
u16 fsw, fcw;
fsw = fcw = 0xffff;
cr0 = read_cr0();
cr0 &= ~(X86_CR0_TS | X86_CR0_EM);
write_cr0(cr0);
asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
: "+m" (fsw), "+m" (fcw));
if (fsw == 0 && (fcw & 0x103f) == 0x003f)
set_cpu_cap(c, X86_FEATURE_FPU);
else
clear_cpu_cap(c, X86_FEATURE_FPU);
/* The final cr0 value is set in fpu_init() */
}
......@@ -91,3 +91,37 @@ void fpu__cpu_init(void)
xsave_init();
eager_fpu_init();
}
static int __init no_387(char *s)
{
setup_clear_cpu_cap(X86_FEATURE_FPU);
return 1;
}
__setup("no387", no_387);
/*
* Set the X86_FEATURE_FPU CPU-capability bit based on
* trying to execute an actual sequence of FPU instructions:
*/
void fpu__detect(struct cpuinfo_x86 *c)
{
unsigned long cr0;
u16 fsw, fcw;
fsw = fcw = 0xffff;
cr0 = read_cr0();
cr0 &= ~(X86_CR0_TS | X86_CR0_EM);
write_cr0(cr0);
asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
: "+m" (fsw), "+m" (fcw));
if (fsw == 0 && (fcw & 0x103f) == 0x003f)
set_cpu_cap(c, X86_FEATURE_FPU);
else
clear_cpu_cap(c, X86_FEATURE_FPU);
/* The final cr0 value is set in fpu_init() */
}
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